Wireless telegraphy and telephony



Sept, 6, 1932. G. WRIGHT WIRELESS TELEGRAPHY AND TELEPHONY Filed Jan. l7. 1928 2 Sheets-Sheet l INVENTOR GEORGE M. WNGHT A ORNEY Sept. 6, 1932.

G. M. WRIGHT 1,876,124

WIRELESS TELEGRAPH! AND TELEPHONY 2 Sheets-Sheet 2 Filed Jan. 17. 1928 Hlllll Xl M XlllllXl INVENTOR GEORGE M- WRIGHT ATTORNEY no mmvmm WRIGHT, or nunroim, ENGLAND, 'Assieivonro 1 Tron" or AMERICA, AcoRronA'rIonor'nnLAwAnn' 1 This invention relates towireless teleg- ,raphy and telephon and more particularly to systems of wireless telegraphy and telephony inwhichla plurality of separated receivingaerialsis provided. V i

a 11011 systems have been employed in endea-vours to obviate; the effects of fading,

for, since these said efiectsdo not appear to occur simultaneously at different points on the earths surface, even when the said points are separated by quite small distances, the

ja a

.1809, the resultant would tend According to this invention in multiple receiving aerial sum total of signalstrength obtained from a plurality of aerials should not be liable to approximate to zero as a result of fading.

all? has been found, howeventhat'simple ,combinationof the signals received upon a urality of aerials does not solve the probblem, owing to the phase difference which imayyojccur at any instantbetween received signals; for example, if, at any instant, the phase dilference betweentwo signals were towards zero.

aerial. receivingtsystems means are provided for comb ning the signals from the aerials na common ciroult, n, such manneras to be a effectively additive irrespective of phase re- .lationship; it i 3 the, oscillators,

such 2 lengths be difficulty that interference between the re- 1 a This :may' be eflected by modulating a reic iv ngh te o yn 51 1 i ome Way pp' g the received signal before combina- In' somecasesthe aerials are located com- ;paratively, close to one another (for examaerials spaced 250 yards apart), and in cases, more especially if short wave employed, there arisesthe further ceiving ,aerialsgis liablet o occur. For exam- .vple, where heterodyne reception employed,

of which there may be four o more operating simultaneously, tend to interfere; with one another and mutual interference is very V -.prone-;to occur where super-regenerative relceiversare employed, for, l such receivers re-radiate strongly.

set up beat tones; Again,

as is well known,

* Preferably, therefore, i carrying out this ceiving install plurality of aerials.

put of whichis passed to a low amplifier and detector24. T

- WIRELESS TELEGRAPHY AND TELEPHONY one receiver is operative at a time.

, i The invention is illustrated in theaccord panying drawings, in which Fig re lrshows n conventlonal diagrammatic form a receivmanner that only nADfo oonroiin Application filed zranuar v, 1928, Serial No. 24,7;350, and in Great Britain January 1'7, 1927 6- mg installation comprising two aerials,-and i Figure 2 a receiving installation comprising four, aerials. Itis, of course, tobe under stood that the inventionis applicable to re- .a ns C mpr s ng y d s Figure 3 illustrates apparatus for carrying out the present invention with a rotating commutator and, R

, Eigureeillustrates apparatus forusing a on theheterodyne prinbeing; con- Referring to vFigure 1, 1, 2 are shortwave 5 is a short wave oscillator which is common to both rectifiers andjwhoseoutput is suppliedv thereto over-feeders err nd receiving system according to the present inyention operating ciple, the receiver oscillations trolled from aicommon generator.

s w h e oup respeccoupling circuits 8, 9,10, Output at super sonic frequency-is passed via feeders;1 1, 12 and coupling circuits 13,14, 15,16, 17 and 18 to thermionic valves 19, 20 whose grids ,are biassed by means of the battery, 21, so that the said valves are normally fying points. Theoutputfrom anhaudioior supersonic frequency oscillator 22 is superimposed through atransformer 2 3:V upon the grids ofthe valves 19, 20 whose anode cirat their recti- 1 I cuits are connected to feed intofacommon supersonic frequency amplifier 23", theoutfrequency It will be seenthat, assuming "oscillator 22 not to be working, no signal will be passed to the amplifier 23, owing'tothe grid bias applied to the valves 19, 20, IVVhen, however, the oscillator22 functions, the grids of the valves 19, 20 will, be driven: alternately positive and negative 2 respectively, so that each said valve will, in turn, effectively couple its associated aerial to the final receiver. In thi s way the signals from: the aerials land 2 are combined independently of'phase.

In the modification shown in Figure 2, there are four spaced receiving aerialsrrepresented at 25, 26, 27 and 28. These aerials are coupled to thermionic valves129,30,31,132

whose anodes are'connected together in pairs by leads 33, Stand upon Whose grid circuits are superimposed means :of transformers 35;361ow frequencyoscillationsfromacomlthe receiver oscillators-may be supplied (for nate'ly in-;leadsj33-and-"3.4c. "Thatis toksay, the

-'appanatus, insoFfarasdescribed', effectively coni'bined-the signalsfrom1aerials25, 26 inde; :pendentlyof phase', ('in lead and also the from aerials 27 28 independently .of .iiphas (anlead3 l); V V e f S-ignals in leadsf33 and 34:areynow;passed :throughcou lingcircuits 39, 4O to-thegrids df fttrther' valves ll, 42, ",WllOSG "grids are 3o biassed by means of a battery-43 in-a manner "similarto that?already described in connecttionnvithval-ves 29, 30, '31, 32 andupon Whose said grids are superimposed,"bymeans of a i t1a Hf0rmer*%l4,- oscillations from a second low ss'rfrequeney oscillator (not' shown) Whose freequency' is*'tvificeithat f the low frequency os illator airway referred to. Output "from the -valves ll, 4e52 ,i'skled tof amplifiers 23f 24L eoorresponding to: the similarlysindicated am- I hearrangement (if-Figure man wvl-ll be ensthat the action of; the valves: 41,

and their co-operatingflow frequency osc i llatoryvvill result inthe combination indeependently ofjphase ofthe V signals, from leads "3225 ,i}26,'?27,-= {28" are combined independently of phase, the-" 'said aerials coming into'eflective "vopcratiomsu'ccessively. W i 1 -Any-th r arrangements'-for"chopping or v 150 otherwiseindependently combining the sig- -na ls f-ro n a":lu-rality of *aerialsf may :be emfployed. For exampleywhen two or more 581611818 and associated oscillating receivers J: "are employed, the-oscillators may be supplied, ifrom-a-plural1tyof note generators fhaving definitephasefiisplacementone to, another, or, alternatively; there may beemployed arotating commutator orlikedevicearranged to rerfder eachrreceiver, operative in turn at an flgaudrblema-te.

"*F gure-S illustrates a-method ofemploying af-modi-fied form of the invention'as disclosed 1ngF1gure-1. Rotation of the commutator O g n! which may be-accomplished in any suitable tery' fOR'rflfiCh pairso'f valves) so thatthe said -28,so*that one oscillatonfunctions duringthe by telephony, I are'rendere'd operativeand inoperative should f'dition,=,the damping beingremove points,

fashion, causes valves 20' and 19 to become conductive alternately.

tery B and the resistance R are short circuited by the commutator. 7 Similarly, and alternately pvalve 20:becomes"condujctivezand am- Again, in a multiple aerial receiving systern; operating .on the heterodyne; pr nc ple,

example, With anode potential) or controlled flOlflIl aeco mmon' note frequency generator in such manner that only one oscillator is Workingata time. IF'or-eizamplaif' theregbe two receivingoscillators, they maybe effectively controlled by th'e'note frequency generator, so that one oscillator functions during the positive half Wave of th-ei generatorfthe "other functioning during the other half-Wave? a methodjof using a e-cenin-g system-"operating on the heterodyne prinj Figure 4 shows 5ciple,"the receiver oscillations-being controlled from the commonnote f'requenoy generator positive half wave from generator 2 8 While lJlIB other functions during the other 1 half -wavel That is, the two'high frequency'oscillators 4:5, 46" are made" to operate, by virtue of varying plate petentials, ;0n' alternate half I As the 'grid biasing V resistance R is high, valvejl9 becoines oonvductive only when the combination of the batcycles of the local oscillator '28. *For the' sake of simplicity,the-rs't'of the st'r'ucture'oifFig uref has beenomitted as it-is' identicalto that I shown'in-Figure 1'. V g l When the-received signals are constituted the" rate athich the receivers besu'person-ic. Such an arrangement' is par- 1 ticularly suitable for application to super-regenerative receivers, all-the said receivers bemg n0rmallyma1nta1nedin quenched conreceiver'lin succession:

Having now particularly described an as- "certaine'dthenature.of*my'said inventionand the same'is'to bee-performed, I declare that Whal'fI claim-1s T in wh at manner 1. Radio signalling apparatus comprising a j 2; Radio'fsignalling apparatus; comprising means for collecting electromagnetic energy of like frequency-at a plurality of'separated lected' near to'each point of collectionwith locally generated electricalenergy,andmeans for translating successively the resulting beatea'rotatlng-commutator, theflillustration being.

'frequency'en'ergies. I V

' 5 3. Radio signalling apparatus comprising means for collecting-relectromagnetic energy of like frequency at a plurality'o'f-separated dfrom each means for beating the ener-g'ies soeole points,means for locally generating electrical energy, means for beating the locally generated energy and the collected energies, and

means for translating the resulting beat fre- 3 5 quency energies successively at a super-audible rate. a a

i 4. In a radio signalling system, the combination of a plurality of collectors collecting energy of like frequency, a local oscillator, means for beating the output of the local oscillator and the energy collected at each one of said collectors, means for feeding the resulting beat frequency energy into a common circuit, electron discharge devices 5 associated with said common circuit, and

another oscillator associated with said electron discharge devices for rendering efl'ective at one time in the output circuit of said electron discharge devices solely energy col- 2o lected uponone of said collectors.

5, In combination, a plurality of separated antennae each collecting energy of like frequency, an electron discharge device coupled to each of said antennae, a pair of electron. discharge devices connected in push-pull fashion, a source of alternating current coupled to the control electrodes of the electron discharge devices connected in push-pull fashion whereby the electron stream in each 0 of said push-pull connected devices is alternately turned on and ofi, circuits for coupling the outputs of each electron discharge devices at each antenna to a pair of input electrodes of said push-pull connected electron discharge devices, and means for translating the output of the push-pull connected electron discharge devices.

GEORGE MAURICE WRIGHT. 

